Combined Embolization/Ablation of RCC in a Solitary Kidney Sirish Kishore, MD Nishita Kothary, MD Division of Interventional Radiology Stanford University School of Medicine

Disclosures Nishita Kothary: Scientific Advisor to Siemens Healthcare, Forchheim, Germany

Case HISTORY OF PRESENT ILLNESS: 63 year old man with history of right nephrectomy for RCC, lost to follow up. CT for prostatitis 14 years after the original surgery, revealed a new asymptomatic 4.5 cm renal mass in the midpole of the left (solitary) kidney, with imaging characteristics of RCC. PAST MEDICAL HISTORY: Right renal RCC PAST SURGICAL HISTORY: Radical right nephrectomy FAMILY HISTORY: None pertinent SOCIAL HISTORY: Former smoker – 15 pack years

Physical Exam & Labs T 36.7 BP: 121/73, Pulse: 61, Resp: 17, SpO2: 98% Gen: No acute distress Cardiac: RRR Lungs: CTAB Abdomen: soft, NT, ND Pertinent Labs : Cr 1.3. Platelets and coagulation factors within normal parameters.

Contrast enhanced CT demonstrates a 4 Contrast enhanced CT demonstrates a 4.5 cm heterogeneously enhancing mass in the midpole of the solitary left kidney.

Clinical Discussion Based on the size and the location of the tumor, the only viable surgical option was radical left nephrectomy with life-long dialysis. The life style changes associated with dialysis were not acceptable to the patient, who opted for ablation despite the higher risk of residual or recurrent tumor.

Clinical Discussion Based on the size of the RCC, a decision was made to embolize the tumor super-selectively followed by cryoablation the next day.

Left renal angiogram (A) and selective angiogram (B) demonstrates the left renal mass that was embolized with a 4 mL mixture of ethanol/lipiodol in a 3:1 ratio. B A

Unenhanced helical CT for ablation planning demonstrates the tumor with ethiodized oil staining within it.

A single axial image demonstrates two cryoprobes (PERC 24, Healthtronics, Austin, TX) in the superior portion of the tumor. Two additional probes (not shown) were placed in the inferior portion. Ablation was performed using a 10 min freeze-7 min thaw -10 min freeze cycle.

Immediate Course There were no immediate complications. Overnight observation was uneventful. Post procedure Cr: 1.4 Discharged with follow up clinic appointment

Follow-up Imaging Contrast-enhanced Ultrasound obtained 1 month after ablation showed no evidence of viable tumor

Contrast-enhanced MRI obtained at 3 months post-ablation and contrast enhanced CT obtained 1 year after the ablation show no evidence of enhancement and decreasing size of the RCC, consistent with no evidence of viable tumor. Cr on last f/u:1.06

Discussion Majority of ablations (RFA/microwave/cryo) are performed for RCCs < 3cm. Prior studies have shown that ablation alone for tumors exceeding 4cm. are at risk for incomplete ablation. Further the risk of hemorrhage following cryoablation increases with size. The use of renal embolization prior to ablation for larger tumors is considered to be instrumental in achieving uniform thermal damage, especially in tumors >4cm. Small studies* have indicated that this combined approach leads to sustained response in tumors that exceed the conventional size criteria. *Arima et al International Journal of Urology, Volume 14, Issue 7 , July 2007